Demand for liquid crystal resins having excellent heat resistance, flowability, electric characteristics, etc., has increased especially for small precision molded articles for electric and electronic applications. Because liquid crystal resins have high thermal stability and high dimensional accuracy at high temperatures, investigations are recently carried out on the use liquid crystal resins in support substrates of heating components, liquid crystal display supporting substrates of office automation equipment and cellular phones, structural components of lamps, and the like.
In most of these applications, resins used come into contact with metal components, such as heating terminals; thus, the resins must not invade the metal components. However, most liquid crystal resins are synthesized by polycondensation by deacetylation or dephenolization and thus generate corrosive gas such as acetic acid or phenol. Accordingly, the use of these resins to the above-described applications has been limited.
With respect to supporting substrates of liquid crystal devices and the like, these gases cause problems such as clouding of display lenses. In particular, phenol gas having low volatility causes clouding such that the glass surface appears to have doubled. When these gasses are generated in large amounts, oligomers are released together with these gasses via the same decomposition process, and clouding of glass surfaces occurs as a result.
In these applications, the resins are sometimes required to engage with surfaces of other components or to withstand the sliding operation with metal components. However, since liquid crystal resins are molded at a high temperature near a decomposition temperature, bulging sometimes occurs in the surface of the resulting molded product by generation of gas, thereby decreasing the yield.
In order to overcome these problems induced by the gasses, studies are conducted to improve the terminal groups of liquid crystal resins so as to decrease the amounts of gasses (for example, Patent Documents 1 to 3).
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2-16150 (pp. 1-2)
Patent Document 2: Japanese Patent Publication No. 3309459 (pp. 1-2)
Patent Document 3: Japanese Unexamined Patent Application Publication No. 11-263829 (pp. 1-2)